The soil backfills were placed against the 11-ft wide by 5.5-ft high side of the pile cap, resulting in a loaded face with an aspect ratio of 2. As shown in the plan view drawing, the backfill zone was approximately 23 ft wide and 28 ft long. The cross-sectional view drawing shows that the soil within the first 8 ft from the cap within the excavation extends to a depth of approximately 7 ft, after which the base of the excavation slopes up to its exit point at the ground surface. The dimensions of the backfill zone were selected to minimize the amount of backfill soil needed while still enclosing the anticipated shape of a log-spiral failure plane in three dimensions